1. Field of the Invention
This invention relates to a locking device for a self-closing closure and more particularly it refers to a locking device forming part of the closure.
Self-closing closures for tubes or the like for dispensing flowable material upon the application of pressure upon the content of the tube have been well known for many years.
Self-closing closures of the kind referred to work very well but when tubes and the like utilizing such closures are to be transported, special arrangements have to be made to prevent leakage as any pressure exerted upon the tube will cause the pressure upon the content of the tube to be raised and if such a pressure is sufficiently high a dispensing takes place.
Attempts have been made to lock the central part of the diaphragm in its closed position but such a locking results in deformation of the thin diaphragm when a pressure is exerted upon the tube and if such a pressure is high, the deformation will be permanent or there occurs a rupture and in both cases the closure will not be able to function in a proper manner.
2. Brief Summary of the Invention
It is therefore the primary object of this invention to provide an improved locking device for self-closing closures.
It is another object of the invention to provide an improved locking device which releases the diaphragm from any stress when in its closed and locked position.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the foregoing objects and in accordance with the purpose of the invention, as embodied and broadly described herein, the self-closing closure for a package comprises a diaphragm member and a central member having a stem which forms a valve with an opening in said diaphragm, the diaphragm member and the central member being connected to each other in peripheral parts thereof and in a manner enabling said diaphragm member and said central member to be angularly displaced relative to each other, the diaphragm member having a tubular portion sealingly surrounding a cylindrical portion of the central member, the tubular portion and the cylindrical portion having openings which in one angular position of the diaphragm member and the central member register to establish free flow communication between the interior of the package and the interior of the closure but which in another angular position of the diaphragm member and the central member are out of registry to prevent flow communication between the interior of the package and the interior of the closure.
It is preferred that the cylindrical portion of the central member is tubular and that the diaphragm member has a peripheral resilient lip which diverges in the dispensing direction of the closure and that said lip is adapted to be snapped into a circumferential groove of a resilient lip included in the central member which in turn is adapted to be snapped into a groove or channel of a package or the like.